Do you need to have the actual ticket when applying for a visa.

My employer is applying for my husband to join me in China on a dependent visa for the duration of my contract that ends in August 2017.

1) Can he buy a one way ticket as he will be living with me in PRC?
2) Most flights go to PRC through the US, so he will need to get a transit type from the US. The US has advises NOT to buy tickets before being granted a transit type in case you are denied. Does the Chinese embassy require the ticket to be bought to get the G type or do they just want to know the expected date of travel?